This invention relates to the field of electromagnetic radiation suppression and attenuation and, more specifically, to electromagnetic radiation shields disposed on removable communications connector components.
Computers and servers are commonly connected to communications networks along with other computers and servers. The network and network connections typically are made with fiber optic cables. On occasion, such networks and network connections may be made using coaxial cable. The connections are made through communications ports in a wall of a system housing and there may be as many as 24 or more such ports on a typical computer or server.
Electrically grounded and serving as an enclosing electromagnetic radiation shield to attenuate, capture and ground the electromagnetic radiation radiated by conductors and electronic components, the system housing is partially prevented from performing attenuation and suppression function by necessary openings in the system housing. A communication port, one of the required openings, creates paths that allow electromagnetic radiation to escape from within the electronic system housing.
Internal electromagnetic radiation shields have been devised to prevent electromagnetic radiation escape from within the main computer housing; however, so long as connectors are required to be inserted into and removed from communication ports, mating connectors and associated signal lines and conductors will be required to be outside the internal shields, and escape paths will exist for unimpeded electromagnetic radiation radiated by the connector interfaces and conductors external to any internal electromagnetic radiation shielding associated with the communications port. The component materials of the transceiver module which interconnects the connector interface with the network data lines are typically not such that they provide adequate electromagnetic radiation shielding as installed and provide no electromagnetic radiation shielding at all once removed.
Dummy plugs with shielding properties have been considered, but they require adequate contact with a grounded component and are subject to being lost or misplaced, therefore not a good solution. Additionally, these dummy plugs are only useful if a transceiver module is removed from the communication ports.
A simple and reliable connection technique must be available to ground the electromagnetic radiation shield to be effective when a transceiver module is inserted into the communication port without any operator action other than simply inserting the transceiver module into a communication port.
It is an object of the invention to provide electromagnetic radiation shielding at a communications port opening in an electronics system housing.
It is another object of the invention to provide a simple and reliable grounding of the electromagnetic radiation shield to prevent electromagnetic radiation escape.
It is a further object of the invention to insure grounding of the electromagnetic radiation shield as a result of insertion of a shield-carrying component that other more expensive shielding may be eliminated.
It is still a further object of the invention to provide such electromagnetic radiation shielding that other more expensive shielding may be eliminated.
It is an additional object of the invention to provide a connection or ground path from the electromagnetic shield to the optical subassemblies when these subassemblies are conductive.
It is still another object of the invention to provide ground path connections to the optical subassemblies through stamped or coined fingers or slots.
Additional objects of the invention may become apparent and be recognized by one skilled in art.
This invention is an electromagnetic radiation shield which permits the projection therethrough of at least one interface and connection barrel of a connector member, thereby permitting the transmission of communication signals through the electromagnetic radiation shield while blocking or at least attenuating any electromagnetic radiation generated within the host electronic system and/or attempting to escape to the external environment.
The electromagnetic radiation shield is preferably a piece of flat sheet metal stock, such as steel or an alloy of steel with at least an aperture therethrough. The aperture is intended and is positioned and dimensioned to accept a barrel of a transceiver optical subassembly of an opto-electronic transceiver or an optical fiber which protrudes through the shield.
The electromagnetic radiation shield must be grounded to properly function in the collection of electromagnetic radiation and disposal of the electrical energy by conducting to ground any electrical current created by electromagnetic radiation in the electromagnetic radiation shield. The opto-electronic transceiver and its structural module must be insertable into and removable from the communication port of an electronic system, such as a computer or server, in order to accommodate both coaxial cable and fiber optic cable network connections. This removable/insertable characteristic of the transceiver prevents a permanent attachment and prevents grounding, by soldering or other permanent attachment techniques, of the electromagnetic radiation shield within the transceiver module to the electronic system enclosure.
In order to facilitate grounding and removal, the electromagnetic radiation shield is provided with a plurality of extensions which project outwardly, extending through openings in the module and beyond the module. The extensions are formed, bent or shaped to present curved spring-like contact portions that will wipingly engage a metal electromagnetic radiation shield structure to ground the electromagnetic radiation shield plate and still remain removable and interchangeable. As a part of the transceiver opto-electronic subassembly, the electromagnetic radiation shield is assembled into the transceiver module frame, which is preferably comprised of mating shells which fit over and receive the extensions, the opto-electronic transceiver and the electromagnetic radiation shield. Whenever the optical subassemblies (OSA""s) are conductive, the electromagnetic radiation shield can make connections and ground the conductive optical subassemblies through the spring members formed by the coined or stamped fingers and/or slots.
A more complete and detailed understanding of the invention may be obtained from the attached drawings and the Detailed Description of the Invention to follow.